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Notes: The adsorption, decomposition, and oxidation of ethanol on Pd(110) has been studied using high-resolution x-ray photoelectron spectroscopy (XPS) and temperature-programmed XPS. The decomposition pathways of ethanol on the clean surface (to methane, hydrogen and carbon monoxide; and to methane, hydrogen, and carbon and oxygen adatoms) previously studied using molecular beam and thermal desorption spectroscopy were confirmed by this study. The presence of an overlayer of oxygen did not significantly alter the major or minor decomposition pathways observed on the clean surface, except for the production of water and, at temperatures above 380 K, carbon dioxide as oxidation products. It also resulted in the formation of acetate, which was first seen during temperature-programmed desorption as coincident carbon dioxide and hydrogen desorption, and was confirmed by XPS. Two C 1s peaks, one assigned to the methyl carbon in acetate and the other to the carboxylate carbon, developed simultaneously during TPXPS. The disappearance of these peaks in XPS occurred at a similar temperature (400 K) to that seen during temperature-programmed desorption. © 1999 American Institute of Physics.

Notes: We have recetitly phenotyped inflammation iti tion-infectious allergic and non-allergic chronic maxillary sinusitis using sinus biopsies and lavage fluids. In this first paper, we have concentrated our work on the eosinophil, T cell, mast cell and macrophage infiltrates. However, many unresolved questions remain and particularly the role of neutrophils needed to be addressed. In the present study, we focused on the neutrophilic inflammation: myeloperoxidase (MPO) and interleukin-8 (IL-8) were measured by immunoassays and neutrophils were enumerated by conventional staining in the sinus lavage fluids of 16 patients with chronic sinusitis and six control subjects. Both MPO and IL-8 levels were significantly higher in patients than in controls (P 〈 0.01 and 0.005, respectively). There was a significant correlation between MPO levels and neutrophil numbers, and between MPO and IL-8 levels in the sinus lavage fluid (P 〈 0.0001, Spearman rank correlation). The presence of high levels of IL-8 in the lavage fluids of patients suffering from chronic sinusitis, levels which correlate with those of MPO, suggests that this cytokine may activate neutrophils in this chronic disease.

Notes: Background Atopic dermatitis (AD) is associated with increased levels of serum igE. and T-helper (Th) cells are thought to a play role in the pathogenesis. Individuals with AD often develop IgE antibodies against the yeast Pityrosporum orhiculare. a member of the normal cutaneous flora.Objective The role of P. orbiculare in atopic dermatitis was investigated by examining the T-cell reactivity for P. orbiculare.Methods Freshly isolated peripheral blood monoruclear cells (PBMC) were isolated from 10 AD patients with serum IgE antibodies against P. orbiculare, and from six healthy controls. The proliferative response after P. orbiculare stimulation, measured by [3H]thymidine incorporation, was examined in the PBMC and in T-cell clones (TCC) obtained from skin and blood of one patient. The cytokine profile of the TCC was determined by enzyme-linked immunosorhent assay (ELISA). radioimmunoassay (RIA) and reverse transcriptase-polymerase chain reaction (RT-PCR) following challenge with either P. orbiculare extract or anti-CD3 antibodies and phytohaemag-glutinin.Results The PBMC response to P. orbiculare was significantly higher in the AD patients than in the control group (P 〈 0.05). Twenty-nine out of 36 tested TCC derived from one responding patient were reactive for P. orhiculare. The clones were CD2+ and CD4+, except for one CD8+ blood clone. A majority of the TCC derived from lesional skin showed a Th2- or Th2/Th0-like cytokine profile. A co-expression of interIeukin-5 (IL-5) mRNA and II-13 mRNA was detected in five out of six P. orhicularc-reative clones analysed for their cytokinc gene expression with RT-PCR.Conclusion Our data suggest that P. orhiculare can induce a T-cell response in AD patients. The Th2-like profile of P. orbiculare-reactive TCC derived from lesional skin indicates that P. orhiculare may play a role in maintaining IgE-mediated skin inflammation in AD.

Notes: Abstract— The random temperature fluctuation produced by the incomplete mixing of hot and cold fluid streams passing over the surface of a component or structure is known as thermal striping. This phenomenon may cause thermal fatigue to occur. It is of particular concern in various types of nuclear reactors, for rapid shut-downs of hot plant and in thermal stratification. A computer code, “TBL”, is a design tool which has been developed to assess thermal striping damage in plates. This model is further developed in this paper to assess such damage in cylindrical components. A recent, universal weight function method is examined and incorporated into TBL. Good comparisons are found between TBL and finite element results for a sinusoidally varying temperature-time-striping history. Potential thermal striping damage is assessed for a cylindrical component of material typically found in the above-core region of a fast reactor under a random temperature-time-striping history.

Notes: Abstract— Thermal fatigue damage may be caused when incompletely mixed hot and cold fluid streams pass over the surface of a component or structure. This kind of thermal fatigue, known as thermal striping, is of particular concern in various types of nuclear reactors and for rapid shut-downs of hot plant. A computer code, known as TBL, is an engineering design tool which has been developed to assess thermal striping damage for fully constrained plates. This model is further developed to account for various plate-constraint conditions. It is compared with two other methods of assessing thermal striping damage. Good agreement is found for the cases when the component is (a) a plate, constrained in various ways and exposed to a sinusoidally varying temperature time striping history and (b) a shroud tube found in the above-core region of a fast reactor pressure vessel and striped with a random temperature time history.

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Notes: [Auszug] Lehner and colleagues reply — We appreciate the alternative interpretation of our data suggested by Gordon Ada and Arno Müillbacher. Complete or partial protection from rectal mucosal SIV infection was found in all seven immunized macaques by targeting the vaccine in the proximity of the ...

Notes: Abstract. The feeding response of juvenile amphipod Gammarus pulex (L.) was investigated following exposure to freshwater pollutants. The method employed is nondestructive, provides a rapid indication of the status of groups of individuals, and is based on a time-response analysis of the consumption of the eggs of Artemia salina and the determination of median feeding times or FT50s. The feeding activity of juvenile G. pulex was found to be a sensitive response criterion for use in assessing the sublethal toxicity of copper, lindane, and 3,4-dichloroaniline (3,4-DCA). Reductions in gammarid feeding activity were identified following 96 hours exposure at 12.1 μg/L copper or 8.4 μg/L lindane and 240 hours exposure at 918 μg/L 3,4-DCA. However, a significant increase was observed in the feeding rate of gammarids that had been exposed for 240 h at 0.09 μg/L lindane in comparison with control values. The increase in feeding rate may be interpreted as a possible stimulatory effect associated with the toxicant action of lindane. Increases in gammarid feeding activity were not determined during the experiments conducted with either copper or 3,4-DCA. A sustained reduction in G. pulex feeding rates may cause growth inhibition and impaired reproduction which have previously been identified as sublethal responses of other freshwater organisms exposed to comparable concentrations of lindane, 3,4-DCA, or copper. The feeding bioassay was also used as a tool in an investigation of species interactions in toxicant systems. The feeding responses of G. pulex, which had been maintained in the presence of Asellus aquaticus (as interacting pairs) and exposed to a range of concentrations of lindane or 3,4-DCA, were recorded and compared. The findings illustrate the complex nature of test systems that integrate the stresses of toxicant and competition. In the lindane test system a reduction in gammarid feeding activity was observed following a 96-h exposure with A. aquaticus at 3.8 and 6.0 μg/L lindane (mean measured concentrations). After a 240-h exposure period a decrease in feeding rate was recorded only for gammarids that had been exposed to 6.5 μg/L lindane, however exposure to very low concentrations of lindane (0.1 and 0.9 μg/L) resulted in a significant increase in gammarid feeding activity. In the experiment conducted with 3,4-DCA the calculation of median feeding times or FT50s of gammarids that had been exposed for 96 and 240 h in the toxicant treatment groups with A. aquaticus was largely precluded (in most groups less than 50% of the A. salina eggs were eaten). However, control group FT50 values were determined on each occasion the bioassay was performed, indicating that a substantial reduction in gammarid feeding activity had occurred in the majority of the 3,4-DCA treatment groups.

Notes: Abstract Alcohol dehydrogenase II (ADH II, structural genealcB) was purified from a strain H1035,biA1; alcE1; alc500 alcD1, which produces 100-times more ADH II activity than thealcAalcR deletion strain (alc500). Antibodies were raised against this ADH, and were used to screen a cDNA library in γgt11. We have isolated the gene for an ADH which is over-expressed in H1035, and which we believe to be thealcB gene; cDNA and genomic clones were sequenced. The sequence contains three introns and encodes a protein of 367 amino acids. This protein shows a clear level of identity to a range of alcohol dehydrogenases, but is no more closely related to the ADH I and ADH III previously described inA. nidulans than to the ADHs ofS. pombe andS. cerevisiae. The significance of consensus sequences found in the 5′ region of the gene is discussed in relation to the regulation of the gene.

Notes: Abstract   Alcohol dehydrogenase II (ADH II, structural gene alcB) was purified from a strain H1035, biA1; alcE1; alc500 alcD1, which produces 100-times more ADH II activity than the alcAalcR deletion strain (alc500). Antibodies were raised against this ADH, and were used to screen a cDNA library in λgt11. We have isolated the gene for an ADH which is over-expressed in H1035, and which we believe to be the alcB gene; cDNA and genomic clones were sequenced. The sequence contains three introns and encodes a protein of 367 amino acids. This protein shows a clear level of identity to a range of alcohol dehydrogenases, but is no more closely related to the ADH I and ADH III previously described in A. nidulans than to the ADHs of S. pombe and S. cerevisiae. The significance of consensus sequences found in the 5′ region of the gene is discussed in relation to the regulation of the gene.